Accumulator device for a flexible element



Jan. 16, 1962 K. K. KNIGHT ETAL 3,017,130

ACCUMULATOR DEVICE FOR A FLEXIBLE ELEMENT OriginalFiled Jan. 17, 1955 INV EN TOR [gm Er A, Ai /awr /If MM J M r/ZZZ H fl ATTO R NEYS.

3,017,130 ACCUMULATOR DEVICE FOR A FLEXIBLE ELEMENT Kenneth K. Knight,604 Forest Ave, and William J. Wenzel, 41 Meadowlark Drive, both ofGreat Falls, Mont.

Original application Jan. 17, 1955, Ser. No. 482,367, now Patent No.2,824,616, dated Feb. 25, 1958. Divided and this application Dec. 6,1957, Ser. No. 701,093

7 Claims. (Cl. 242-4709) This invention relates to an accumulator devicefor a flexible element and this application is a division of ourcopending application, Serial No. 482,367 filed January 17, 1955, nowPatent No. 2,824,616.

In the above mentioned copending application we disclosed an automaticself-steering vehicle which carried a length of flexible element such asa wire and which was arranged to lay this wire down as the vehicleproceeds. Means are provided to pick the wire up in front of the machinefrom a previously laid course so that once the machine is put inoperation it moves along with it steering mechanism guided by sensingthe position of the previously laid down wire which is being picked up,while at the same time the vehicle lays down additional wire indisplaced relation. In this way the vehicle may be used to pull a mower,for example, and to mow an entire field starting at the periphery andending at the center.

The accumulator device for the wire which is disclosed and claimed insaid copending application constitutes the subject matter of the presentapplication.

It is therefore the principal object of the present invention to providean accumulator for a great length of flexible element such as wire,which may be paid out therefrom and taken up therein at variable anddiffering rates. It is thus another object of the invention to provide adiiferenti-al accumulating reel from which a length of flexible elementmay be paid out and onto which a length of flexible element may bewound, wherein said flexible element may be paid out at a faster orslower rate than it is being taken up and wherein the rates of payingout and taking up may be constantly changed.

It is another object of the invention to provide a ditferential reelwhich will automatically and differentially take up and pay out flexibleelement while storing and accumulating any flexible element being takenup in excess of that being paid out.

These and other objects of the invention which will be described in moredetail hereinafter or which will become apparent to one skilled in theart upon reading these specifications we accomplish by that certainconstruction and arrangement of parts of which we shall now describe anexemplary embodiment.

Reference is made to the drawings forming a part hereof and in which:

FIGURE 1 is a plan view of an accumulator reel according to theinvention.

FIGURE 2 is a diametral cross-sectional view of the same.

FIGURE 3 is an elevational view of the same.

FIGURE 4 is a bottom view of the winding on element; and

FIGURE 5 is a fragmentary cross-sectional view of the same taken on theline 5-5 of FIGURE 4.

For the details of operation of the device with which the presentinvention may be used, reference is made to the copending applicationabove referred to. It will of course be understood that the device is ofutility in any situation where a flexible element must be taken up andpaid out at varying rates, with a provision for the accumulation orstoring of the flexible element. Referring first to FIG URE 3, theaccumulating reel is indicated generally at R.

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The wire which is being taken up passes over a series of pulleys 30, 31and 32 and thence about the induction device 10, 11 (used in chargingthe wire according to the said copending application) and thence ontothe reel. The wire being paid out passes over pulleys 33, 34 and 35. Thepulleys 31 and 34 are mounted on arms 36 and 37 upon which arerespectively also mounted pulleys 38 and 39. The arms 36 and 37 areunder tension of the springs 40 and 41.

At 42 and 43 are shown pulleys which are continuously driven at aconstant speed, as for example from a power take-off from the primemover of the vehicle, and these pulleys by means of belts 44 and 45drive the pulleys 46 and 47.

In the case of the incoming wire W it will be clear that as long asthere is no resistance to the taking up of the Wire, the spring 40 willurge the roller 38 against the belt 44 so as to maintain drivingtension. If there is resistance to taking up of the wire W the roller 38will be pulled away from contact with the belt 44, permitting the beltto slip so that the pulley 46 ceases to be driven.

In the case of the outgoing wire, the situation is reversed, in that thepulley 39 maintains driving tension on the belt 45 only so long as thereis pull on the wire W When there is no pull, the spring 41 pulls theroller 39 out of contact with the belt 45, permitting it .to slip andceasing to drive the pulley 47.

Turning now to FIGURE 2, we have shown the two pulleys 46 and 47 whichare adapted to be driven by the belts 44 and 45 and it will beunderstood that the pulley 46 is turning when wire is being taken up,while the pulley 47 turns only when wire is being paid out, and it willbe understood that that speed of the pulleys 46 and 47 is proportionalto the rate at which the wire is being taken up and paid out,respectively.

On a platform 50 bearings are provided for four rollers 51 which aresymrnertically disposed. Each of the rollers 51 is provided with a smallgear 52 by means of which it may be rotated. The four gears 52 areadapted to mesh with a large sun (gear 53 having a beveled gear 54'integral therewith and having a central internally threaded sleeve 55.Threaded into the sleeve 55 is an externally threaded element 56 whichis connected by means of a spline 57 to a gear '58 coaxial with thegears 53 and 54. Secured to the member 56 is a wire feeding arm 60 whichextends radially outward and then downward and which is preferablytubular so that the incoming wire W may pass through it. The individualrollers 51 are provided with helical grooves to accept the wire as it iswound around them.

The gear 58 is arranged to be driven by the gear 61 which is secured tothe cage of the differential. The difierential has an input gear 62driven by the pulley 46 and an input gear 63 driven by the pulley 47, sothat the gear 61 constitutes the output of the differential. The pulley47 also drives a gear 64 which meshes with the gear 54 described above.

In describing the operation of this device, let it be assumed first thatno wire is being paid out but that wire is being taken up. From what hasgone before, it will be understood that under these conditions thepulley 46 will be rotating and the pulley 47 will be stationary. Thepulley 46 drives the gear 62 and since the pulley 47 is not rotating,the gear 63 is not rotating. By the action of the differential, theentire input of the gear 62 is transmitted to the cage and the cage gear61, and from the gear 61 the drive is transmitted to the gear 58 whichthrough the splined connection 57 causes the member 56 to rotate. As itrotates by virtue of its threaded connection with the member 55 whichunder these conditions is stationary, the member 56 is moving upwardly.As

the member 56 rotates and moves upwardly, the gear 70, which will bedescribed hereinafter, at the end of the arm 60 is caused to orbitaround the four rollers 51 and move upwardly at the same time todescribe a helical path. Thus, the wire W entering the arm 60 is by thisaction wound helically around the fourrollers 51. At this point it maybe well to mention that because of the rotation of the arm 60, a twistis imparted to the Wire W The function of the gear 70 is to remove thetwist. The gear 70 has a bearing on the end of the arm 60, as best seenin FIGURE 5, and it meshes with the partial internal gear 71 whichextends the full height of the reel, and is fixed to the inside of thecasing of the reel R. As the arm 60 rotates, the gear 70, engaging thestationary gear 71 once in every revolution of the arm 60, rotates in areverse direction so as to take out of the wire the twist which was putinto it by the rotating of the arm 60.

Now let us assume that no wire is being taken up on the reel but thatwire is being paid out. Under this hypothesis, the pulley 46 and thegear 62 are stationary while the pulley 47 is rotating and, therefore,the gear 64 and the gear 63 are rotating. Rotation of the gear 64 istransmitted through the gear 54 to the'gear 53 and thence to the foursmall gears 52. so that each of the rollers 51 is caused to rotate aboutits own axis to feed the wire W ofl from the bottom.

It will be understood that because the wire lies in helical grooves onthe rollers 51, the locus at which the wire W came off would becontinuously rising. This, however, is avoided because of the fact thatthe gear 63 is rotating and the entire input of the gear 63 istransmitted to the cage gear 61 which drives the gear 58 in the oppositedirection. The opposite rotation of the gear 58 is transmitted throughthe splined connection 57 to the member 56 which is caused to rotate inthe opposite direction so that the wire is beingcontinuously unwrappedat the top from the rollers 51 as it is being fed ofl the bottom. Thus,the wire is always fed off the bottom and if no wire is being taken up,the rotating arm 60 simply lowers the level of the stored wire at thetop.

If wire is being reeled in and paid out at equal rates, it will be clearthat the gears 62 and 63 will be caused to rotate in opposite directionsso that the cage gear 61 and the gear 58 and the member 56 will notrotate and the level of stored wire will remain stationary. It will beclear from what has gone before that the reel will always store oraccumulate the difference between the amount of wire being taken in andthe amount being paid out.

The operation of winding the wire onto the rollers 51 by rotation of thearm 60 inducesya twist into the wire and this twist is taken out of thewire by means I of the gear 70, as best seen in FIGURES 4 and 5 and asdescribed above.

It will be clear that numerous modifiications may be made in details ofour invention and that the specific embodiment described is to beconsidered as being by way of example only. We do not intend to limitour selves in any manner other than as set forth in the claims whichfollow.

Having now fully described our invention, what we claim as new anddesire to secure by Letters Patent is:

1. A differential reel for storing a great length of a flexible elementwhich is adapted to be taken up on said reel and paid out therefrom atdiflerent and changing rates, comprising a frame, a plurality of rollerssymmetrically disposed with their axes parallel and having bearings insaid frame, each of said rollers having a helical groove for seating aportion of said flexible element, a gear secured to each of saidrollers, a common gear meshing with each of said roller gears forconcurrently -rotating all of said rollers in the same direction, aninternally threaded sleeve coaxially secured to said common gear, anexternally threaded member in threaded engagement with said internallythreaded sleeve, a flexible element feeding arm secured to saidexternally threaded member and extending radially beyond the peripheriesof said rollers, a splined shaft for rotating said externally threadedmember, a gear secured to said splined shaft, a differential having oneinput controlled by the flexible element being taken up and a secondinput controlled by the flexible element being paid out, and an outputin driving relation with said splined shaft gear, and a gear driven bysaid second input and in driving relation with said common gear.

2. A device according to claim 1, wherein said feeding arm is tubular,said flexible element being taken up on said reel passing through saidarm, said arm terminating in a rotatable throat, and means for rotatingsaid throat to remove from said flexible element the twist impartedthereto by the rotation of said arm.

3. A device according to claim 2, wherein said throat is a bore in agear rotatably mounted on the end of said arm, said gear meshinginternally with a ring gear having an axial extent to accommodate saidthroat gear throughout the range of feeding movement of said arm.

4. An accumulating device for a long length of a flexible element whichis adapted to be fed into and paid out from said device at rates whichmay differ and which may vary, comprising a reel for storing a portionof said flexible element in the form of helical convolutions, means forwrapping additional amounts of said flexible element onto said reel inhelical convolutions, said wrapping means comprising an arm rotatableabout and feedable along the axis of said reel, said arm being tubularand said flexible element, which is fed into said device, passingthrough said arm, said arm terminating in a rotatable throat, means forrotating said throat to remove from said flexible element the twistimparted thereto by the rotation of said arm, means for advancing saidhelical convolutions along said reel topay out a portion of said storedflexible element from one end of said reel so as to maintain asubstantially fixed locus from Whichsaid flexible element is being paidout, means for actuating said advancing means in proportion to the rateat which said flexible element is being paid out, and a diflerentialgear drive means for actuating said wrapping means in proportion to thedifference between the rates at which said flexible element is fed intoand paid out from said device.

5. A device according to claim 4, wherein said throat is a bore in agear rotatably mounted on the end of said arm, said gear meshinginternally with a ring gear having an axial extent to accommodate saidfirst named gear throughout the range of feeding movement of said arm.

6. An accumulating device for a long length of a flexible element whichis adapted to be fed into and paid out from said device at rates whichmay differ and which may vary, comprising a reel for storing a portionof said flexible element in the form of helical convolutions, means ifor wrapping additional amounts of said flexible element onto said reelin helical convolutions, means for advancing said helical convolutionsalong said reel to pay out a portion of said stored flexible elementfrom one end of said reel so as to maintain a substantially fixed focusfrom which said flexible element is being paid out, means for actuatingsaid advancing means in proportion to the rate at which said flexibleelement is being paid out, and a differential gear drive means foractuating said wrapping means in proportion to the diflerence betweenthe rates at which said flexible element is fed into and paid out fromsaid device, said differential means having two inputs and wherein bothinputs are driven through belt drives, said belt drives being driven byan independent power means and having for each belt an idler pulley andmeans for urging said idler pulley against its respective belt toproduce power transmission, one of said idler pulleys being spring urgedto operative position and adapted to be pulled out of operative positionby tension in said flexible element being taken up, the other of saididler pulleys being urged to operative position by tension in saidflexible element being paid out, and spring urged to inoperativeposition where there is no tension on said flexible element beng paidout.

7. An accumulating device for a longth length of a flexible elementwhich is adapted to be fed into and paid out from said device at rateswhich may differ and which may vary, comprising a reel for storing aportion of said flexible element in the form of helical convolutions,means for wrapping additional amounts of said flexible element onto saidreel in helical convolutions, said wrapping means comprising an armrotatable about and feedable along the axis of said reel, means forrotating said arm about said axis, means for feeding said arm along saidaxis, means for advancing said helical convolutions along said reel topay out a portion of said stored flexible element from one end of saidreel so as to maintain a substantially fixed locus from which saidflexible element is being paid out, means for actuating said advancingmeans in proportion to the rate at which said flexible element is beingpaid out, a diiferential gear drive means for actuating said wrappingmeans in proportion to the difierence between the rates at which saidflexible element is fed into and paid out from said device, saiddifferential having two input elements and an output element, means forrotating one input of said differential at a rate of speed proportionalto the rate at which said flexible element is being taken up, and meansfor rotating the other input of said differential at a rate of speedproportional to the rate at which said flexible element is being paidout, whereby the output of said differential is proportional to thedifference between said rates, means for actuating said rotating andfeeding means concurrently in a wrapping direction at a rate of speedproportional to the output of said diflerential, and means for actuatingsaid feeding means only in a reverse direction in proportion to the rateof speed at which said flexible element is being paid out.

References Cited in the file of this patent UNITED STATES PATENTS1,960,743 Junkers May 29, 1934 2,742,737 McElroy Apr. 24, 1956 FOREIGNPATENTS 539,200 Great Britain Sept. 1, 1951

